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51.
Storyline-based summarization for news topic retrospection   总被引:2,自引:0,他引:2  
Electronics newspapers gradually become main sources for news readers. When facing the numerous reports on a series of events in a topic, a summary of stories from news reports will benefit news readers in reviewing the news topic efficiently. Besides identifying events and presenting news titles and keywords the TDT (Topic Detection and Tracking) techniques are used to do, a summarized text to present event evolution is necessary for general news readers to review events under a news topic. This paper proposes a topic retrospection process and implements the SToRe (Story-line based Topic Retrospection) system that identifies various events under a news topic, and composes a summary that news readers can get the sketch of event evolution in the topic. It consists of three main functions: event identification, main storyline construction and storyline-based summarization. The constructed main storyline can remove the irrelevant events and present a main theme. The storyline-based summarization extracts the representative sentences and takes the main theme as the template to compose the summary. The storyline summary not only provides readers enough information to understand the development of a news topic, but also serves as an index for readers to search corresponding news reports. Following a design science paradigm, a lab experiment is conducted to evaluate the SToRe system in the question-and-answer (Q&A) setting. The experimental results show that SToRe enables news readers to effectively and efficiently capture the evolution of a news topic.  相似文献   
52.
Highly porous Ti and TiZrV film getters on (100) silicon substrates, grown by the glancing angle deposition of dc magnetron sputtering method, were used to study the activation process. The effect of activation temperature on the reducing degree of the porous Ti and TiZrV films were investigated by synchrotron radiation photoemission spectroscopy (SRPES). Elemental carbon absorbed on the surface of the Ti film, exposed in air, will be transformed to a Ti carbide phase, however, that which is on the surface of the TiZrV film will be completely removed by heat at 250 °C or above. The oxidized Ti in a porous TiZrV film is more easily reduced than that in the porous Ti films. The breakdown of V-O and Ti-O bonds on the TiZrV film surface is easier than that of the Zr-O bond. We suggest that the decrease of reducing temperature of oxidized TiZrV, comparing with that of oxidized Ti, is caused by the displacement reaction of Zr on oxidized Ti or oxidized V.  相似文献   
53.
This paper presents a novel NTSC video sync separator (NSS) with a high-PSR (power supply rejection) bias generation circuitry (BGC) which comprises a temperature compensation circuitry. The proposed BGC utilizes step-down regulators and a bandgap-based bias with cascode current control. The clamping voltages required for sync separation from an NTSC signal are generated. Detailed PSR analysis of the proposed BGC is also derived to circumscribe the clamping voltage variation. The proposed design is carried out using 0.35 μm 2P4M CMOS process. The measurement results verify that the HSYNC, the composite signal, and the Line 21 caption data can be separated successfully even if a 1 V noise is coupled in the supply voltage. The measured power consumption of the proposed chip is 31.92 mW.  相似文献   
54.
Distance education courses must cope with the difficulties imposed by delivering a class at a distance. As most courses only emphasize the cognitive aspects of the class and neglect the course’s effect on the students, this gives no help for reaching the affective domain teaching goals. Especially for younger students, in distance education, when younger students are out of the sight of teachers, they could easily be distracted by the environment around them. This research outlines a synchronous discussion procedure with reinforcement mechanism designed for elementary school students to integrate the affective aspects of teaching into distance education within a class period. The mechanism allows teachers to understand students’ attitudes within the class and provides instant feedback to the teacher. Learners can also get information about their attitudes and help to reach the affective domain teaching goals of the courses. This mechanism was implemented and investigated. Comparative assessments were made by administering interviews and questionnaires to elementary school students. The results show that the procedure can supervise learners and help them reach the response stage of the affective domain teaching goals.  相似文献   
55.
20 mol% Gd-doped ceria (20GDC) electrolyte films on poly-crystalline Al2O3 substrates were prepared by radio frequency (RF) magnetron sputtering from a 20GDC oxide target, which was made by the processes of colloidal dispersion-pressure casting-sintering. Material characteristics of the 20GDC oxide target and the deposited films before and after annealed at 900 °C for 2 h were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), and conductivity measurements. Crack-free and dense 20GDC electrolyte films were observed by the deposition conditions of 200 W (RF power). Homogeneity tests revealed the chemical compositions (Ce and Gd) were uniformly distributed through the bulk of the target and the deposited films. 20GDC film with a comparable conductivity of 1.00 × 10− 3 S/cm at 650 °C is higher than that of bulk yttria-stabilized zirconia (YSZ), but smaller than that of bulk GDCs (10GDC and 20 GDC). Sputtered-GDC films in this study can be also suggested to be used as the electrolyte films for solid oxide fuel cells (SOFCs) systems as compared to the well-known YSZ.  相似文献   
56.
The Assumed mode method (AMM) and Finite element method (FEM) were used. Their results were compared to investigate the coupled shaft-torsion, disk-transverse, and blade-bending vibrations in a flexible-disk rotor system. The blades were grouped with a spring. The flexible-disk rotor system was divided into three modes of coupled vibrations: Shaft-disk-blade, disk-blade, and blade-blade. Two new modes of coupled vibrations were introduced, namely, lacing wires-blade and lacing wires-disk-blade. The patterns of change of the natural frequencies and mode shapes of the system were discussed. The results showed the following: first, mode shapes and natural frequencies varied, and the results of the AMM and FEM differed; second, numerical calculation results showed three influencing factors on natural frequencies, namely, the lacing wire constant, the lacing wire location, and the flexible disk; lastly, the flexible disk could affect the stability of the system as reflected in the effect of the rotational speed.  相似文献   
57.
The global positioning system (GPS), which provides accurate positioning and timing information, has become a commonly used navigation instrument for many applications. The application of a new adaptive all-pass based notch filter (ANFA) for narrowband/FM interference suppression and frequency estimation in GPS receivers is proposed. An ANFA structure that achieves better unbiased characteristics with its coefficients is employed to accurately estimate the narrowband interfering signals in online fashion. A variable convergence factor that optimizes the maximal mean square error (MSE) reduction in each iteration is applied in a modified adaptive Gaussian–Newton (MAGN) algorithm. The proposed MAGN algorithm can lead to both faster convergence speed and higher estimation accuracy. Simulation results show that the ANFA offers a better performance than conventional linear predictors in terms of the SNR improvement and the mean output power (MOP) under the interference environments of interest.  相似文献   
58.
Shieh DB  Su CH  Chang FY  Wu YN  Su WC  Hwu JR  Chen JH  Yeh CS 《Nanotechnology》2006,17(16):4174-4182
A comprehensive totally aqueous phase synthesis of nickel-nitrilotriacetate (Ni-NTA) modified superparamagnetic Fe(3)O(4) nanoparticles is presented. The Fe(3)O(4)-NTA-Ni nanoparticles are able to perform efficient and specific purification of 6-His tagged proteins from crude cell lysates, as evidenced by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) and Western blot analysis. The average binding capacity, as demonstrated by streptopain (M(W) 42?kDa), is 0.23?mg/mg (protein/Fe(3)O(4)-NTA-Ni). Considering the high affinity and specificity of the binding between hexahistidine motif and Ni-NTA, Ni-NTA modified nanoparticles could act as a module to carry 6-His tagged proteins on the particle surface with molecular orientation control, since only the 6-His domain could be attached. These modularly designed functional nanoparticles enhance cancer cell targeting, as supported by the in vitro receptor mediated targeting assay using RGD-4C-6-His fusion peptide. The nanoparticles show no significant hemolysis for human blood and could be investigated further for their in vivo functional imaging applications.  相似文献   
59.
Colloid processing and subsequent pressure filtration were used to prepare 14.3 mol% TiO2 doped Bi2O3 (Bi12TiO20, 14BTO) as solid oxide fuel cell electrolyte. Materials characterization and electrical behaviors of 14BTO samples were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and two-point probe DC conductivity. A pure 14BTO with a cubic sillenite single phase was prepared at the sintering process of 850 °C with a high relative sintered density of 96.82%. In situ and batch-type long-term conductivity measurements at 600 °C were carried out to verify the possible reason of degradation. Additional reduction-oxidation tests under CH4 atmosphere by thermogravimetric analysis (TGA) revealed possible application temperature of 14BTO electrolytes below 700 °C.  相似文献   
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